In envelope-filling technology nowadays, the documents are mostly printed and processed so as to be 2-up, that is to say having two documents beside one another. The documents mostly have the standardized format of DIN-A4, letter or legal, and are printed in a portrait style (on end). On the other hand, in envelope-filling technology nowadays envelope-filling is preferably carried out into envelopes which have the opening and thus the envelope flap on the long side. In order to process applications in which the documents are folded in order to be packed into envelopes of the C5, C6/5, or similar formats, on account of folding the short edge of the portrait-fed initial document automatically becomes the long edge of the folded format. The document, which has been infed in the portrait style having the short edge leading, may thus be packed in the folded format having the long edge leading into the envelope.
If, for example, documents infed in the portrait format are to be packed unfolded into a C4 envelope on one and the same machine, the documents have to be rotated by 90° in order for them to be able to be conveyed and envelope-filled having the long edge leading (landscape style) and without having to deflect said documents by 90° (i.e. to convey them onward in a lateral manner), which then would prevent processing of folded applications. The direction of rotation, to the right or to the left, is mostly determined by the position of the window in the envelope.
It is proposed in patent CA1077534 (family: DE2829221A1/U.S. Pat. No. 4,155,440A) titled “Document Turning Station” to rotate a document by 90° by way of a plurality of rollers which are disposed parallel to one another and rotate at different speeds. Rotation here takes place about a corner of the document. In this variant of rotation the center axis is thus permanently displaced in the conveying direction.
DE 10219569A1 titled “Rotating installation of an ID card” a rotating installation which by means of rotating balls and a stop rotates ID cards about said stop. This method has the disadvantage that it can be employed only for rigid objects; a single document would be bent and damaged, a stack of documents could not be processed as it would slide apart. Moreover, the method is reliant on conveying the object to be rotated along a curved edge, which is not possible with a corner of a sheet of paper.
In U.S. Pat. No. 5,114,137 titled “Right Angle Turn Table and Method” a rotating installation for rotating documents by means of two conveyor belts which operate at different speeds is described. The long space requirement, the inaccurate rotation requiring subsequent lateral alignment, which in the case of thin sheets may often lead to a rising of the edge and thus to disruptions are disadvantageous. Furthermore, a stack of documents cannot be processed using this solution, since the document on the lower side merely bears on two belts and on the upper side is merely guided by light rollers. Moreover, a stack of documents would slide apart when impacting the stop roller which initiates the rotation. Furthermore, there is the risk of damage to the edge of the sheet by the stop which initiates the rotation and about which the document is rotated.
In DE 102007054822A1 a “Device for rotating flat objects, in particular blanks for folding boxes” is proposed. On account of the free rotation said device is not suitable for rotating light sheets of paper which, on account of their very light dead weight, would shift out of place in an uncontrolled manner. Rotating a stack of sheets is not at all possible, since said stack would also internally shift out of place. The unit requires a large space. The alignment of the entire unit which is additionally required in order to achieve a good rotation result, for optimization moreover requires a large number of identical objects to be rotated, while in the case of the requirements of the present remit various thicknesses and numbers of sheets may occur from one object to another.
The object of the present invention lies in proposing a further solution for rotating sheet-type products, such as, in particular, documents individually or in stacks, letters, and the like, which enables an increased throughput rate in the case of the rotating operation, requires little space, enables a variable thickness to be processed and also processing of a plurality of loosely stacked documents, and all this without permanently displacing the conveying axis.
According to the invention a device and a method as disclosed herein are proposed.
The present invention proposes a solution by way of which this rotating operation can be performed at a significantly higher throughput rate and less strain on both the documents and the machine elements.
The objects to be rotated are individual documents or document groups of a plurality of documents which are stacked on top of one another or, in more general terms, two-dimensional objects. Elsewhere, these may also be envelopes, non-filled, filled, having an open or closed flap. The documents or document groups are infed into the chain of the entry modules in the portrait style (longitudinally). The rotating device has the task of rotating the documents/document groups by 90°, selectively in a clockwise or counter-clockwise manner, so that said documents/document groups can subsequently be infed in the landscape style (transversely) to the enveloping module. Of course, the rotation from landscape to portrait or of equilateral documents or those of non-rectangular shape is also possible. Documents which are already delivered in the correct orientation, that is to say folded documents for example, have to be able to be conveyed by the rotating device without rotating.
The center of the document should lie both ahead of the rotation and after the rotation on the same axis. During the rotating operation, the center of the document can travel along a curve of any desired shape, however.
Stopping the documents with subsequent on-the-spot rotation during start-stop operation requires a relatively large amount of time; cycle times which are required in the future can therefore no longer be achieved. A principle is therefore required which rotates the documents in a controlled manner by 90° in the desired direction within a short time, but without permanently displacing the document laterally in the process and optionally also allowing documents which are not to be rotated to be conveyed onward.
The rotation of the documents is implemented by two roller pairs which rotate at different speeds and in this manner set the document (or the document group) which is clamped between the rollers into a rotating movement. The two drive-roller pairs may in each case dispose of a separate drive.
It is proposed that the roller pairs, oriented toward the same conveying direction, rotate at different speeds and conveying of the documents is not interrupted, i.e. that no start-stop operation takes place, as is known in part from the prior art.
Further variants of embodiments of the device and also of the inventive method are characterized in the dependent claims.
The invention is now explained in more detail in an exemplary manner and with reference to the appended figures.